Customizing the LinGO Grammar Matrix Morphology

Abstract Blends of polycaprolactone (PCL) and poly(3-hydroxyoctanoate) P(3HO) were prepared by melt compounding. These immiscible blends exhibited droplet-matrix morphology at compositions up to 30 wt% P(3HO). Even though the addition of amorphous P(3HO) decreased the crystallinity of PCL, the crystallization temperature of the blends increased by 6 to 7 8C. Blends containing up to 30 wt% P(3HO) had higher crystallization rates, and lower crystallization half-times compared to neat PCL. The viscosity of PCL decreased upon addition of P(3HO), making the blends suitable for processing using a 3D bioplotter. Compositions with 10 to 30 wt% P(3HO) were ideal for processing, because of their improved crystallization kinetics, reduced stickiness and good flow properties. Estimation of the interfacial tension by fitting the Palierne model to the linear viscoelastic properties of the blends revealed good compatibility, which gave rise to synergistic effects in the thermal and mechanical properties. The fibres prepared by 3D bioplotting maintained droplet matrix morphology, with finer particle size than the original compounded material. In addition to favourable viscosity and thermal properties, the extruded fibres containing 30 wt% P(3HO) had comparable modulus to the neat PCL, while exhibiting good ductility. These blends may be suitable alternatives to PCL for biomedical applications, because they provide a range of crystallinities, crystallization rates and viscosities.

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Chemical adsorption of D-sucrose on MWCNTs for compatibility improvement with alanine-based poly(amide-imide) matrix: morphology examination and thermal stability study

Colloid & Polymer Science ◽

10.1007/s00396-015-3753-y ◽

2015 ◽

Vol 294 (1) ◽

pp. 239-246 ◽

Cited By ~ 2

Author(s):

Shadpour Mallakpour ◽

Vajiheh Behranvand

Keyword(s):

Thermal Stability ◽

Stability Study ◽

Chemical Adsorption ◽

Matrix Morphology ◽

Thermal Stability Study

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Characterization of the Matrix Morphology in Si3N4 Ceramics Formed with Different Additives

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.89-91.477 ◽

1993 ◽

Vol 89-91 ◽

pp. 477-482

Author(s):

H. Björklund ◽

L.K.L. Falk ◽

J. Wasén

Keyword(s):

The Matrix ◽

Matrix Morphology

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The Influence of Carboxy Methyl Cellulose (CMC) and Solution pH on Carbon Fiber Dispersion in White Cement Matrix

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.493.661 ◽

2014 ◽

Vol 493 ◽

pp. 661-665 ◽

Cited By ~ 5

Author(s):

Ari Yustisia Akbar ◽

Yulinda Lestari ◽

Gilang Ramadhan ◽

Septian Adi Candra ◽

Eni Sugiarti

Keyword(s):

Aqueous Solution ◽

Carbon Fiber ◽

Methyl Cellulose ◽

Cement Matrix ◽

Solution Ph ◽

Fiber Dispersion ◽

Reinforced Composite ◽

Disperse Carbon ◽

Reinforced Cement ◽

Matrix Morphology

Dispersion of carbon fiber in cement matrix is one of main challenges for fabricating carbon fiber reinforced cement based materials. In this study, the dispersion of carbon fiber was improved by pre-dispersion of carbon fiber in basic aqueous solution using different concentrations of CMC. The relationships of CMC concentration and pH solution toward carbon fiber dispersion in aqueous solution was evaluated by UVvis spectroscopy. In order to understand how carbon fiber is dispersed in cement matrix, morphology fiber carbon reinforced composite was examined. Experimental results show that aqueous solution of CMC is effective to disperse carbon fiber. In addition, dispersion of carbon fiber increases with increasing of pH of CMC solution.

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Effects of Knit Stretching and Matrix Crystallinity on the Fatigue Behaviour of Knitted Fabric-Reinforced Gf/Pet Composites

Advanced Composites Letters ◽

10.1177/096369359700600303 ◽

1997 ◽

Vol 6 (3) ◽

pp. 096369359700600 ◽

Cited By ~ 2

Author(s):

E. Moos ◽

J. Karger-Kocsis

Keyword(s):

Endurance Limit ◽

Damage Zone ◽

Stress Transfer ◽

Fatigue Behaviour ◽

Knitted Fabric ◽

The Matrix ◽

Static Tensile ◽

Matrix Morphology ◽

Number Of Cycles ◽

Fatigue Endurance

In this study the tension-tension fatigue behaviour of weft-knitted glass fibre fabric-reinforced polyethylene terephthalate (GF/PET) composites was studied as a function of the stretching ratio of the knit The knits were stretched prior to consolidation in wale direction in 0, 25, 50 and 73%, respectively, in order to increase the anisotropy and to alter the mechanical properties of the composites. The influence of the matrix morphology (crystalline, amorphous) on the fatigue response was also investigated by using a composite with unstretched knit reinforcement. The results, displayed in normalized maximum fatigue stress Ms number of cycles (S-N) diagrams showed that the fatigue endurance limit of the GF/PET composites did not depend either on the knit stretching or the matrix crystallinity. The fatigue endurance limit, normalized to the static tensile strength, was found at ≍27 and ≍50 % for the knitted fabric-reinforced composite sheets tested in wale (W) and course (C) direction, respectively. The damage zone seemed to be localized for 1 and 2 rows of loops in C-and W-directions, respectively. This failure mode reflects the stress transfer and redistribution capability of the plain weft-knit reinforcement

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The diffusion of long-chain molecules through bulk polyethelene

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1979.0006 ◽

1979 ◽

Vol 365 (1720) ◽

pp. 53-73 ◽

Cited By ~ 106

Keyword(s):

Polymer Melt ◽

Appreciable Effect ◽

Interfacial Resistance ◽

Chain Molecules ◽

Surface Migration ◽

The Matrix ◽

Activation Energy For Diffusion ◽

Matrix Morphology ◽

Entangled Polymer ◽

Long Chain

This paper describes an experimental study of the centre of mass diffusion of linear hydrocarbon or deuterocarbon molecules, of the type (CH 2 ) N or (CD 2 ) N , through bulk polyethylene. N was varied between about 15 and 1500. The diffusion coefficient D was measured as a function of temperature, matrix morphology and diflfusant chain length, both in semi-crystalline and molten polyethylene. The technique used involved labelling the diflfusants so that they absorbed radiation in the infrared spectrum in a region relatively free of absorption by the matrix. Infrared microdensitometry was used to measure diffusion broadening of a known diffusant concentration distribution, and hence to evaluate D . The method avoids problems presented by interfacial resistance and surface migration effects and can also account for the effect of diffusant polydispersity. The diffusion was found to be Fickian and essentially independent of concentration, for the diflfusants used, up to 2%. The data indicate that the morphology of the disordered interlamellar region can have an appreciable effect on the mobility of long-chain diffusants. They also suggest that the activation energy for diffusion in the melt becomes independent of diflfusant length beyond a certain lower limit. The results provide support for de Gennes’s (1971) model of snake-like motion (reptation) for polymeric diflfusants in an entangled polymer melt, and suggest that such motion persists down to a diflfusant size of some 30-(CH 2 )-backbone units.

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